Ford Fiesta Brake Bulb Size

Ford Fiesta brake bulb specifications include 3157 and 1157 sizes for various model configurations. The replacement chart covers vehicle production years spanning 1978 to 2019.

The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.

Bulb Size by Year Range

Years	Bulb Size
2014-2019	3157
1978-1980	1157

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Dual-filament wedge bulb (T25). 12V, 27W/7W.	3157
ANSI standard (US & Canada). Dual-filament bulb with BAY15d bayonet base. 12V, 21W/5W.	1157

Other Locations

Additional Notes

The Ford Fiesta brake light specifications cover two distinct bulb types across the listed model years: the 3157 for 2014-2019 and the 1157 for 1978-1980.
The 3157 is an ANSI-standard dual-filament wedge bulb in the T25 form factor, rated at 12V with a 27W high filament and 7W low filament, making it suitable for combined stop and tail light functions.
The 1157 is an ANSI-standard dual-filament bulb rated at 12V with a 21W high filament and 5W low filament, and it uses a BAY15d bayonet base rather than a wedge-style fitting.
Because the 3157 uses a wedge base and the 1157 uses a BAY15d bayonet base, the two bulb types are not physically interchangeable despite both being dual-filament 12V units.
The wattage difference between the two types is notable: the 3157 draws 27W on its high filament compared to the 1157's 21W, meaning the two bulbs produce different light output levels even when operating on the same circuit voltage.
Both bulb types conform to ANSI standards applicable in the United States and Canada, indicating they are designed to meet North American automotive lighting regulations.
The dual-filament design in both bulb types allows a single housing position to serve two lighting functions simultaneously, typically stop and tail, by switching between the two filaments.
The BAY15d base of the 1157 features two offset pins that prevent incorrect insertion orientation, a design characteristic that distinguishes it from the wedge-style seating of the 3157.